Process of recovering gamma globulins from human blood serum



Patented Mar. 2, l948 ,PROQESS .OF RE-.CQYERING GAMMA .GLQEU- tttrts MAN t John W. illnms and Harold Deutsch, Manli- Ason, Wis., @ssikgpoljs to the United States of 1st as mts?. ted by. the tfttttttzy 1f at No Drawing. Application October 23, 1945, V Sreral Nm what# (C1-26911.12)

This invention rola-tts .t0 .2 method o f reootzduring and tot." lhhue ait?? .tltffltt efrlng Strom gamma glnbulins and more partiou- 8.09.0 units Qi @Empf f Y tac? .logral lmlyjtb th@ application O f ths'metlllod f0.0 the 4leof II-l-lllfpreolpjete. gre Qotlttry .QI gama-glohulins fromoertain by-prod- Vconsists principally Qt ihm uct irootions obtained .from `the processof p re- 5 carded. It Ais rtmotedby statt? paring normal .human albumin. suspension ttt .tt ttly S195?? .tt .'.lhe largoiscale separation of ithealbumin fracf liters per v tion fromhuman hloodplasma foruse'as ablood The effluent from gth ,@pqve precipitate YShhs.that@ and .in t

he ttttttmtnt `of shook has brought to. o salt Qohttttxttitzo made ayailable. as by-prodhts: the serum glob- 19 liter andtheh @i5-. 52 19.5? ttl? ttlttttf ttt# ulns. 'In one large .frenotionwhl'ch lis known as acetate buffer which has o `molo ratio 'of fraction `Ill-111. .therefore separated some ofthe Ciotti soitutitote of 0.15. LF.

beta and ,prootitally all' of theanlma globulins. Venently dott@ .by atldtlf ttPOttt *25. A plombier of the anthoos againsta .variety ,0f s2 t191 1" 5M G @tf1- 7 te. k x pathogenic `ogfrlts ahdwtherhhtigens ale aSSO- ...lh .ISF-1 g @t 'tfllttt catedwith .oractually .tfohsisv of gamma globulin'. '5" a Thus. y.it .becomes :of hraotal imnontane to sep.- arate .the gomma ,globulin .from .the lil-imposte. and industrial procedures have been developed@ oreal; this ifrotioh into' three sub-inaction Home). on vIII-.1 sontoins Some sommo between and fil-5 C- globulih .ih mstuxe with beta globulin. and fra- The @tti tfjmttt ptthittt. hon 1.1172 ,is largely hetazggohmin whtohis zich 1 concert-tr' A L in prothrombin, Y pilhg as adjtste'cl for The procedure for glotgigwlirng the foregoing frao- 2 (5.1-5.3) fnd' the' t tions does not form 'afartof'ths invention but 'n sed to a" roi' is set forth below'to--inustrate .themanner'in which the' required starting vmaterials are pro;

thisooncentrationofethanora precipitate 'forms 3 5 oon'tahsm "slt of'thlsollemgglhtln l ature' between: pf

procinto@ 114-111 ture 'may b betweeny -5 apa-9 of, anddurijg ously but in such a way that it does not foam. A precipitate (II) is formed which consists largely of gamma-globulins, and contains most of the antibodies for which tests have been carried out, excepting those mentioned as present in III-1. It can be removed by centrifugation of the above suspension at a temperature between 5 and 9 C., and at a rate of about l0-50 liters per hour. It may be dried from the frozen state. The shell-freezing of the material is somewhat easier if it is suspended in about an equal volume of water, half of which has been frozen just before mixing.

The fraction III- 1 obtained by the above described method has, heretofore, been considered a waste product and until the disclosure of the process of enzymatic hydrolysis or digestion of human serum globulins by J. W. Williams, M. L. Peterman and W. B. Bridgman in the copending application, Serial Number 623,796, led October 22, 19115, no method was available for the eiicient recovery from it of the immune gamma globulins. The process disclosed in the copending application involves digesting gamma globulins with certain proteolytic enzymes to break down the gamma globulin molecule to units of one-half and one-quarter size without impairing the important antibody reactions. Since it has been found to be possible to fractionate the digest system more or less into the different size categories, there exists new and important methods for further concentration and purification of the immune bodies. The foregoing method, however, is somewhat diliicult to carry out in large scale operations owing to the enzymatic digestion step. Furthermore, existing commercial procedures for obtaining serum gamma globulins are characterized by low yields. One such method provides a yield of from 40-50% gamma globulin while another provides only from 2535%.

It is the principal object of this invention to provide a simple, inexpensive process for recovering serum gamma globulin which affords high yields. Another object of this invention is to provide a process for recovering serum gamma globulin directly from the fraction II-l-III globulins obtained in the preparation of normal human serum albumin. Still another object of this invention is to provide a method of recovering serum gamma globulin having good stability, high purity and the requisite immunological assay.

This invention is based on the ldiscovery that a suspension of a paste containing both beta and gamma globulins in a medium in which the ionic strength is maintained at the low level of 0.010 to 0.015, the pH at 5.13i0.05, and the alcohol concentration of 15 to 17% forms a solution containing a large portion of the gamma. globulin without the gamma globulins being salted-out from said solution, The method comprises suspending the fraction II-l-III paste in pyrogenfree water, preferably about liters for each kilogram of paste and adjusting the hydrogen ion concentration to pH 4.0 to 5.1. This suspension is allowed to stand up to twenty-four hours during which time it may be stirred. In the case of fraction III-1 pastes, the initial suspension may be prepared by adding the paste to a small vol- -ume of an aqueous solution of sodium chloride, increasing the volume of the suspension by adding pyrogen-free water, preferably enough to bring the volume to about 18 liters for each kilogram of paste suspended, and thereafter adjust- 'ing the pI-I of the suspension to 4.0 to 5.1. Following the period in which II-l-III or III-1 suspensions are allowed to stand, the hydrogen ion concentration Vof the suspension is adjusted to pH 51310.05 and the volume of the suspension further increased, preferably to about 20 liters for each kilogram of paste suspended. All pH values are measured at 25 C., and before alcohol additions.

The suspensions prepared by the methods described above are then ltreated by introducing ethanol until an ethanol concentration of from 15 to 17 is reached. The ionic strength of the suspension following the addition of ethanol must be maintained at a low level, e. g., from 0.010 to 0.015, lto accomplish the desired result. The ionic strength must be maintained between these values and the pH must be carefully controlled if high yields of gamma globulin are to lbe obtained. A precipitate forms following the addition of ethanol which consists largely of beta globulins. The suspension is stirred for from one to two hours and is then centrifuged at a temperature just above the freezing point of the solution. The eiiiuent is then ltered through a thin pad of a suitable filter aid and sodium bicarbonate solution added thereto until the pH is from 7.0 .to 7.2. Ethanol is then added to the eiliuent until the ethanol concentration is approximately 20 to 25%. A precipitate forms which consists largely of gamma globulins. These gamma globulins contain many of the immune bodies. This precipitate may be removed by centrifuging. These gamma globulins may be then suspended in Water, shell frozen and dried by standard methods, The process described above must be conducted in the cold at all times. It is especially important that low temperatures be maintained during the steps of adding ethanol to the suspensions.

In order more clearly to disclose the nature of the present inventio specific examples will hereinafter be described in considerable detail. It should be clearly understood, however, that this is done solely by way of example and not for the purpose of restricting the scope of the appended claims.

' Example I Each kilogram of fraction III 1 precipitate is suspended in 10 liters of 0 C. pyrogen-free water. This suspension should be stirred and kept at a temperature of 0 C. as 460 ml. .of 0.05 M acetic acid is slowly added. The pH of the solution should be 4.80i0-05 after this addition is completed. After stirring for 1-2 hours at 0 C., a mixture, again at 0 C., of 4500 ml. 0.05 M acetic acid and 3250 ml. 0.05 M NazHPOi is introduced into the system. The solution then should have pH=5.13i0.05.

The solution containing 1 kg. .of paste is now brought to a volume of 20 liters with 0 C. pyrogen-free water and stirred for one hour. The ethanol concentration is brought to 17% by the addition of 9.1 liters of 53.3% alcohol. The ionic strength of the suspension following the addition of ethanol is 0.013. During this addition the temperature is kept as low as possible without freezing and it should be 6 C. when 17% concentration is reached. After stirring for one hour at this temperature the precipitate is removed by centrifugation, again at 6 C.

The eiiiuent is filtered through a thin pad of a suitable lter aid. After the pH of the ltered eluent is adjusted to 7.1i0-1 by the addition of 650 ml. of 0.5 M NaI-1G03, the alcohol concentration is brought to 20 to 25% with 95% ethanol,

arrestenVK Treatment Yield Electrophoresis Per cent Ionic Experi-` Grams ment EtOH Strength. Gamma `pH Hours 'Globulin a B2' ,S1 alb.

Al4A 4.16l 14 17 0.013 14.2 98 l 0 1 A-1GB 4.92 16 17 0.010 14.4. 94 3 0 3 A-19 4.86 17 17 0.014 13.5 99 0l 0 1 Example II Y Each kilogram of a fraction n+1-1I precipitate is suspended in 8 liters of 0 C. :pyrogen-free water. In order to bring the pl-i of the system to 4.801005 there is added 43000 ml. of 0.05 M acetic acid always keeping the system at C. After the solution has been slowly stirred `for periods up to'twenty-,four hours Yat 0' C., a mixture of 3400 ml. 0.05 M acetic acid and 34001111. of 0.05 M Naai-11304 is added, again at 0 Cf., to bring the pI-I to 5.13i0.05,

The solution .containing 1 kg. of paste is now brought to a volume of 25 liters with 0 C. pyrogen-free Water and stirred for one hour. The ethanol concentration is brought `to 17% by the addition of 11.25 liters of 53.3% alcohol. The ionic strength following this addition of ethanol is 0.012. During this addition the temperature is kept as low as possible without freezing and it should be 5 C. when V17% vconcentration is reached. After stirring for one hour at this temperature the precipitate is removed by centrifugation, again at 6 C.

The effluent is filtered through a thin pad of a suitable nlter aid. After the pI-I of the filtered eluent is adjusted to 7.li0.1 by the addition of 900 ml. of 0.5 M Naf-1G03 the alcohol concentration is brought from 20 to 25% with 95% ethanol, pre-cooled to 5 C. or colder. The precipitate formed is removed by centrifugation at a temperature not higher than 5 C. It lis dried from the frozen state in the usual manner.

The precipitate obtained in this manner has a purity of some 95% in gamma globulins and represents a yield of approximately 75%.

The results obtained by several experiments performed employing 200 grams of fraction II-l-HI paste are given in the following table:

Treatment Yield Electrophoresis Experi- Per cent Ionic in ment EtOH Strength Grams pH Hours a B2 51 alb.

A-7 4.80 l0 17 0.012 18.8 97 2 0 1 A-BC.- 4. l2 17 0.015 17.6 97 2 0 1 lil-9B.- 4.70 0.3 17 0.014 16.3 97 2 0 1 Example III Each kilogram of fraction 114-111 is suspended in 10 liters of 0 C. pyrogen-free water. In order to bring the pI-I of the system to pH 4.8i0-05 there is added 4850 ml. of a dilute pI-I 4.0 solution. (This solution is prepared by adding 680 ml. of

purity of 95% a yield of approximately 70-7 5%.

Vabout 900 ml- Yof 0.050 MNafI-lPOi .to-41710 ml. .of (1;050 N acetic acid.) After the system has beenslowly stirred overnight at 0 C., a buffer mixture of 264.0 ml. of V0.050 M Na2HPO4 and 2260 ml. of '0;050 N acetic acid is added, again .at-'0 C., to bring :the pH to 5131-005.

'The solution containing l kg. .of paste is now brought to a volume of 25.0 liters with 0 C'. pyrogen-free water.. The ethanol concentration is brought to 1.7% :by the addition `of 11.25 liters of 53.3% alcohol. The ionic .strength .is 0.012 at this point. During this addition the temperature is kept as low .as possible without freezing; it should be 16.5 C. when 17% concentration is reached. After -stirring for one hour .at this temperature the precipitate, a new III- 1 residue, is removed by centrifugation, again at 6.5 C.

The eiiiuent is filtered through a thin pad of suitable filter aid. After the pH of .the filtered efuent is adjusted to 7.1i0;1 by the addition of `0.50 M NaI-1G03, the alcohol concentration is brought to 25% with `95% ethanol, pre-cooled lto 5 C. or colder. vThe .precipitate, gamma globulin, is removed by centrifugation at a temperature not higher than 5 C. It is vdried from the frozen state in the usual manner..

The precipitate obtained in this manner has a in gamma globulin-and represents 'Having thus described our invention, what we claim as new and wish to secure by Letters Patent is:

1. The method of recovering human serum gamma globulinsl which contain immune bodies from mixtures of human serum beta and gamma globulins which comprises, forming a suspension of a mixture of human serum Ybeta and gamma globulins, `adding la compound selected from an acid and acid buffer solution to adjust the pH to from 4.0 to 5.1, adjusting the pH Vto from 5.08 to 5.18, stirring said suspension, adding 0 C. pyrogen-free water containing suicient electrolyte to provide a predetermined low level of ionic strength until the Volume is approximately 20 liters per kilogram of 'said mixture suspended, adding ethanol until the ethanol rconcentration is from 15 to 17% and the ionic strength is 0.010 to 0.015 to precipitate the rbeta globulins, kcentrifuging to remove said precipitate, adjusting `the pH of -the effluent to from 7.0 to 7.2, adding ethanol Vto said eiiiuent until the ethanol concentration is from 20 to 25% to globulins, andcentrifugi-ng lto recoverfsaid gamma globulins.

2. The method of recovering human serum gamma globulins which contain certain immune bodies from mixtures of human serum beta and gamma globulins which comprises, suspending a mixture of human serum beta and gamma globulins in from 8 to 12 liters of 0 C. pyrogen-free water per kilogram of said mixture, adjusting the pI-I to from 4.0 to 5.1, stirring said suspension, adjusting the pH to from 5.08 to 5.18, adding 0 C. pyrogen-free water containing dissolved electrolyte in amount sufcient to provide a predetermined low level of ionic strength, the said water being added to give a Volume of 25 liters per kilogram of said mixture suspended, and 53.3% aqueous ethanol until the ethanol concentration is from 15 to 17% with a resultant ionic strength of 0.010 to 0.015 to precipitate the beta globulins, centrifuging to remove said precipitate, adjusting ethanoi until the ethanol concentration of precipitate lthe gamma said eiiiuent is from 20 to 25% to precipitate the gamma globulins, and centrifuging to recover said gamma globulins.

3. The method of recovering human serum globulins from mixtures of human serum beta and-gamma globulins which comprises, suspending a mixture of human serum beta and gamma globulins in C. pyrogen-free` water in the proportion of from 8 to l0 liters per kilogram of said mixture, adding dilute acetate buier solution of pH 3.5 to 4 until the pH is 430x005, stirring for from 1 to 2 hours at 0 C., adding a solution made up by adding 2640 ml. of 0.05 mole of disodium phosphate and 2260 ml. of 0.05 mole of acetic acid until the pH is 5.13i0.05, stirring said suspension, adjusting the volume with 0 C. pyrogenfree electrolyte solution to 20 liters per kilogram of mixture suspended, adding 53.3% ethanol until the ethanol concentration is approximately 17% and the ionic strength is 0.010 to 0.015 to precipitate the beta globulins, stirring, centrifuging at a temperature of -6 C. to remove said precipitate, filtering the effluent, adding sodium acid carbonate solution to said eiiiuent until the pH is 7.1i0.1, adding 95% ethanol until the ethanol concentration is approximately 20 to 25% to precipitate the gamma globulins, and centrifuging at a temperature of C. to recover said gamma globulins.

4. The method of recovering human serum gamma globulins which contain certain' immune bodies, from mixtures of humamserum beta and gamma globulins, Which comprises suspending a mixture of human serum beta and gamma globulins in pyrogen-free water, adjusting the hydrogen ion concentration oi the suspension to pH 4.0 to 5.1, allowing the resulting suspension to stand for approximately twenty-four hours, adjusting the hydrogen ion concentration of the suspension to pH 5.13i0-05, introducing ethanol into the resulting adjusted suspension until an ethanol concentration of from substantially fifteen per cent to seventeen per cent is reached, maintaining the suspension at an ionic strength of from 0.010 to 0.015 following the addition of the ethanol, stirring the resulting suspension for substantially one to two hours, centrifuging the suspension at a temperature just above the freezing point of the solution, ltering the suspension, adding sodium bicarbonate solution to the resulting eiiiuent until the solution reaches a pH value of from '7.0 to 7.2, adding ethanol to the said eluent until the ethanol concentration is from approximately twenty per cent to twentyve per cent, and recovering the resulting precipitate which ulins.

5. The method of recovering human serum gamma globulins which contain certain immune bodies, from lmixtures of human serum beta and gamma. globulins, which comprises adding the paste of human serum in an aqueous solution of sodium chloride, increasing the volume of the resulting suspension by adding pyrogen-free water to bring the volume of suspension to approximately eighteen liters for each kilogram of paste suspended, adjusting the pH value of the resulting suspension to pH 4.0 to 5.1, allowing the resulting suspension to stand for twenty-four hours, then adjusting the pH value of the suspension to pH 5.l3i0.05, further increaslng the volume of the suspension to about twenty liters for each kilogram of the paste suspended, adding ethanol to the suspension until an ethanol concentration of from approximately fteen per cent to seventeen per cent is reached, maintaining the resulting suspension at an ionic strength of approximately 0.010 to 0.015 following the addition of the ethanol, stirring the resulting suspension for from approximately one to consists essentially of gamma globtwo hours, centrifuging the suspension at a temperature just above the freezing point of the solution, filtering the suspension, adding sodium bicarbonate solution to the resulting eiliuent from the filtering until the said eiiluent has a pH value of from 7.0 to 7.2, adding ethanol to the said effluent until the ethanol concentration is approximately twenty to twenty-live per cent, and recovering the resulting precipitate of gamma globulins by centrifuging, suspending in water, shell freezing and drying, the entire process being carried out at temperatures not substantially exceeding 0 C.

JOHN W. WILLIAMS. HAROLD F. DEUTSCH.

REFERENCES CITED The following references are of record in the lile of this patent:

UNITED STATES PATENTS OTHER REFERENCES Cohn, Chemical Reviews, vol. 28, pages 395 to 417 (1941).

Cohn et al., J. Am.

Chem. Soc., vol. 62, pages 3396 to 3400 (1940). n

beta and gamma globulins 

